Forms burster



Sept. 1, 1964 c. L. PETERSON FORMS BURSTER 5 Sheets-Sheet 1 Filed Dec.3l, 1962 #EFL C. L. PETERSON FORMS BURSTER Sept. 1, 1964 5 Sheets-Sheet2 Filed Dec. 5l, 1962 Sept. l, 1964 c. L. PETERSON 3,146,927

FORMS BURSTER Filed Deo. 5l, 1962 5 Sheets-Shea?l 5 FIE 5 SePfl, 1964 C.L. PETERsoN 3,146,927

FORMS BURSTER Filed Deo. 3l, 1962 5 Sheets-Sheet 4 Sept. l, 1964 c.PETERSON FORMS BURSTER 5 Sheets-Sheet 5 Filed Dec. 3l, 1962 UnitedStates Patent O 3,146,927 FORMS BURSTER Charles L. Peterson, CrystalLake, Ill., assigner to Uarco Incorporated, a corporation of IllinoisFiled Dec. 31, 1962, Ser. No. 248,476 11 Claims. (Cl. 22S-100) Thisinvention relates to stationery processing mechanisms and moreparticularly to a bursting device for separating form lengths fromcontinuous form stationery.

Bursting machines have been developed which utilize the principle of twosets of timed rollers for separating the individual form length from thecontinuous form. These rollers are provided with ats in order to allowstationery to pass freely therebetween at periodic intervals so as tosubstantially eliminate bubbles which may appear in the surface of thestationery being fed through the machine. Usually the most rearward ofthe two sets of rollers is driven at a faster speed than the other setand has a number of flats on the periphery thereof, which in relation tothe number of flats on the other set of rollers, is inverse to the ratioof the speed of the rearward set of rollers to the speed of the otherset of rollers. In order to adapt the bursting machine for burstingcontinuous form stationery of different form lengths, the intermediateset of rollers must be movable relative to the rearward set of rollers.It is important that the timed relationship between the two sets ofrollers is not lost. Bursters have been developed such as thoseillustrated in the co-pending application of Robert M. Pine and DonaldI. Steidinger, Serial No. 210,982, led July 19, 1962, entitled Bursterfand owned by the assignee of this invention, in which a different meansis provided for moving the intermediate set of rollers' relative to therearward set of rollers without interfering with the timed relationshiptherebetween.

It is therefore an object of this invention to provide a new andimproved burster device.

It is another object of this invention to provide a new and improvedburster having an intermediate roller unit which is adjustable relativeto a fixed rear roller unit to vary the space therebetween for variousform lengths of stationery while maintaining a predetermined timedrelation between the units.

It is' still another object of this invention to provide a new andimproved burster having two roller units therein, the first roller unitbeing adjustable relative to the second roller unit to vary the spacetherebetween for adapting the burster for various form lengths ofstationery, the first set of rollers being manually adjustable andself-locking at any preselected position.

VIt is a further object of this invention to'provide a new and improvedburster mechanism having two roller units therein driven by a commonpower source; the rear roller unit being in a fixed position in theburster and the front roller unit being mounted on a pivoted arm andmanually laterally adjustable relative to the rear unit and self-lockingin any preselected position to adapt the unit for processing continuousform stationery of different form lengths; both roller units having aplurality of longitudinal flats thereon with the front roller unit beingdriven at a reduced speed relative to the rear roller unit, the ratio ofthe speed of the rear and intermediate roller unit being inverse to theratio of the number of flats on the individual rollers of the rear andintermediate roller units.

Other objects, features and advantages of the present invention will bereadily apparent from the following description of the preferredembodiment illustrated in the accompanying drawings, in which:

FIGURE 1 is a broken side elevational view partially ICC diagrammatic ofa burster unit embodying this invention; FIGURE 2 is a top plan View ofthe device shown in FIGURE 1;

FIGURE 3 is a fragmentary broken side elevational view of the deviceshown in FIGURE 1 taken from the opposite side thereof;

FIGURE 4 is an enlarged fragmentary view showing the breaker rollassembly;

FIGURE 5 is a vertical section view of the device of this inventiontaken generally normal to the path of stationery travel therethrough;

FIGURE 6 is a fragmentary enlarged section view taken along the line 6-6of FIGURE 1 showing the front roller mounting in detail; and

FIGURE 7 is an enlarged fragmentary section view taken along the line7-7 of FIGURE 2.

The burster 10 of this invention is enclosed in a generally rectangularframe 11 as shown in FIGURES 1 and 2. The burster is adapted to receivea zigzag folded stack 12 of continuous form stationery 12a which isdeposited on a shelf 13 at the front end 19a thereof. From the stack 12the continuous form stationery 12a is driven through the burster in thedirection indicated by the arrow A in FIGURE l. The stationery is fed inthe paper guide means 14 at the front end infeed or channel 15 thereof.The guiding means directs the stationery during its path of travelthrough the driven front and rear roller units, 16 and 17, respectively.The front and rear roller units are operably associated, as will beexplained later, and cooperate to separate the continuous formsstationery into individual form lengths 12b which are deposited on ashelf 1S at the rear end 10b of the burster. A paper holding device 19is pivotally mounted on the burster above the rear shelf 1S for holdingthe individual form lengths 12b thereon.

Mounted within the frame 11 and positioned at the bottom thereof is amotor 20 having a motor pulley 21 mounted on one end of the motor shaft20a. A motor pulley drive belt 22 interconnects the motor pulley 21 andthe drive shaft pulley 23 for supplying rotation thereto. The driveshaft pulley 23/is mounted at one end of the drive shaft 24 whichextends across the bottom of the burster at the mid-point thereofsubstantially transverse to the line of paper travel. Mounted on thedrive shaft 24 at one end thereof is a rear drive roller drive shaftpulley 26 which is interconnected with the rear drive roller pulley 27by a belt 28 for supplying rotational force thereto. Mounted on theother end of the drive shaft 24, opposite from the pulley 26, is thefront drive roller drive shaft pulley 29 which is interconnected withthe front drive roller pulley 30 by a belt 31 for supplying motive forceto the front drive roller unit 16.

Each roller unit 16 and 17 is provided with a pair of verticallyIadjacent'rollers extending generally transverse to the path of papertravel, such `as top rollers 34 and 34a, respecitvely, which arepositioned above the line of paper travel, and bottom rollers 35 and35a, respectively, which are positioned below the line of paper travel.The aforementioned top rollers have a means for releasing the grip onthe stationery :at periodic intervals, or longitudinally extending flats36. In the preferred embodiment of this invention the rear rollers 34aand 35a are driven at twice the speed as the front rollers 34 and 35 andthus the rear roller 34a has half as many flats thereon as the frontroller 34. An actual two-to-one ratio is not necessary so long as theratio of the speed of the two roller units is inverse to the ratio ofthe number of flats on the individual rollers and these -rollersmaintaina timed relationship so that the ilat on roller 34 and one of the ats onroller 34a are in opposed lrelationship to their respective lower rollerat the same time. This permits any bubbles or anv build-ups in thestationery which might occur to periodically pass on through the rollersand thus eliminate one of the major causes of jamming of burstermachines or creasing of continuous form stationery. Each of the rollersis also provided with a plurality of longitudinally spaced areas ofreduced diameter 37 which permit elements of the guiding means 14 topass through the roller units `and continuously throughout the path oftravel of the stationery through the burster.

Each of the rollers 34 and 35 and 34a and 35a have axially mountedoutwardly extending spindles 38, 39, and 38a and 39a, respectively,which have meshing spur gears 40 and 41, and 40a and 41a, respectively,mounted thereon on the ends opposite from their respective drive pulley.The front unit drive pulley 27 is mounted on the lower front unit rollerspindle 39 and rotation of this spindle causes rotation of lthe lowershaft gear 41 at the end opposite from the pulley which is in meshingengagement with the upper shaft gear 40, thus driving both rollers ofthe unit. Similarly, the rear drive roller pulley 27 is mounted on thelower rear roller spindle 39a. Rotation of the pulley 27 thus rotatesthe lower spindle 39a which has mounted on its opposite end the spurgear 41a in meshing engagement with the gear 40a of the upper rollershaft 38a, thus driving both rollers of the rear roller unit 17.

The intermediate roller unit 16 projects laterally outward from arcuateslots 59 and 59a formed in the side walls of the frame and is mounted ateach end thereof on the arms 42 and 42a which are pivotally mounted onthe drive shaft casing 25. The means by which the aforementioned rollersare journaled for rotation is illustrated in detail in FIGURE 6. Theupper `and lower drive spindles, 38 and 39, respectively, are journaledin bearings 43 and 44, respectively, and are spaced apart by means of acoil spring 45 interposed therebetween. The lower bearing 44 is securedto the Iarm 42 but the upper bearing 43 floats relative thereto heldapart from the lower bearing 44 by the aforementioned spring 45.Positioned in the arm 42 above the bearing 43 is the drive rolleradjusting means 46 for adjusting the distance between the spindles 38and 39 and, therefore, the peripheries of the rollers 34 and 35.

The adjusting means 46 includes a manually operated screw 47 having abiasing member 48 threaded thereon. The biasing member 48 comprises anut having one face which is angled relative to the longitudinal extentof the screw shank. Positioned between the biasing member 48 and theupper bearing 43 is -a variable spacing member 49. The spacing member 49comprises a spacer block or wedge having one face also angled relativeto the shank of the screw member 47 and mating with the biasing member48. As the screw 47 is turned and the biasing member 48 is drawn upalong the shank thereof the cooperating wedging action of the matinginclined surfaces of the biasing member 48 and the spacer 49 cause aresultant lateral movement in a direction generally perpendicular to thescrew shank. Since the adjusting' means housing member 49a prevents thelateral movement from being applied in a direction thereabove it must bedirected therebelow to the upper roller bearing housing 43 which pressesagainst the spring means 45 thus bringing the peripheries of the rollers34 and 35 in closer proximity to each other.

The rear roller unit 17 is rotatably journaled at each end in bearingblocks 50 and 50a which are mounted at the rear of the burster. Theblocks 50 and 50a are cornmonly secured to each side of the bursterframe 11 by bolts or screws 51 to form the unit 17. Roller unit 17 isprovided with an adjusting means similar to the adjusting means 46 ofroller unit 16.

As shown in FIGURE 5, a sleeve 54 is concentrically mounted on the driveshaft 24 and bearings 55 are interposed between the sleeve and shaft ateither end thereof permitting rotation of the sleeve relative to thecasing. The sleeve 54 is similarly positioned within a circumferentiallysurrounding cylinder 56 having flanges 56a at either end through whichbolts 57 pass to secure the cylinder, which thus houses the sleeve 54and the drive shaft 24, to the burster frame 11. The -roller unit arms42 and 42a are secured to the sleeve 54 by pins 58, thus making the armsrotatable or pivoted relative to the drive shaft 24. This mounting doesnot disturb the operable relation between the drive components, namelythe drive shaft pulley 29 and the roller unit pulley 30, since thepulley 30 is mounted on the roller shaft 39 and is therefore fixedrelative to the arms 42 and 42a which are pivotal relative to the pulley29. Thus when the arms 42 and 42a are pivoted about their mounting toposition the roller unit 16 at preselected points of stationary travel,the ltimed relationship between the rollers of the roller unit 16 and 17are not disturbed since the arms pivot about a common center with thatof the pulley 29 so that the individual rollers of the roller unit 16are not rotated during such pivotal movement of the arms.

Positioned on the top of the roller unit 16 and extending thereacross isthe front roller unit positioning and locking means 61. This locking andpositioning means 61 is provided for changing the relative distancebetween the front unit 16 and the rear unit 17 to adjust the burster forbursting continuous form stationery having individual form lengths ofdifferent dimensions. The positioning and locking means 61 includes apair of parallel spaced bars 62 and 62a extending across the path ofpaper travel and spaced thereabove. The bars 62 and 62a are eachpivotally secured at their respective ends by means, such as pins 63, tothe upright arms 42 and 42a. Resilient means, such as a spring 64, isinterposed between the bars 62 and 62a at each end thereof andyieldingly urges the bars apart, causing the upper surfaces 65 and 65aof each end of the bars 62 and 62a, respectively, to Contact the upperinner edge 66 and 66a of the arcuate slots 59 and 59a, respectively,thus frictionally locking the roller unit 16 in preselected positions onthe path of travel of the stationery through the burster. An upstandinghandle 67 and 67a is provided at the mid-portion of each bar 62 and 62a,respectively, to permit squeezing by hand pressure to bring the barstogether in opposition to the resilient means 64. This causes the barsto turn inwardly about their pivotal mounting and brings the surfaces 65and 65a out of frictional engagement with the inner arcuate edges 66 and66a. Thus the roller unit 16 may then be freely moved along the path ofstationery travel by pivoting the unit about its mounting with thesleeve 54. Upon release of the handles 67 and 67a the resilient means 64then urges the bars 62 and 62a apart relative to each other about theirpivotal mountings and brings the surfaces 65 and 65a into frictionalengagement with the arcuate edge 66 and 66a, respectively, to mount theroller unit in any preselected position along the path of stationerytravel through the burster.

As shown in FIGURE 7 an appropriate scale 68 may be provided above thearcuate slot 59 for providing means for measuring the relative distancebetween the two roller units. In particular, this scale may be graduatedinto form lengths of stationery which the burster is adapted to burstwhen the front roller unit 16 is at any given position along the lengththereof.

Positioned at the rear of the front roller unit 16 and between theroller units 16 and 17 is a stationery breaker means 70. The breakermeans 70 includes a supporting bar 71 extending across the path of papertravel and spaced thereabove and secured at each end to the arms 42 and42a. The generally L-shaped breaker roller shaft mounting bar 72 issecured therebelow by a securing and adjusting screw 73 which extendsthrough the supporting bar 71 and mounting bar 72 in threaded engagementtherewith. The mounting bar 72 has a leg portion 72a extending below thepath of paper travel and generally parallel thereto. The breaker rollershaft 74 is rotatably journaled at either end in the leg portion '72aand has a plurality of breaker rollers 7 5 mounted thereon. Resilientspacer means such as spring 76 and 76a are interposed between thesupporting bars 71 and mounting bar 72 for cooperating with the securingand adjusting screw 73 to maintain the bars in a preselected position.By turning the screw '73 the two bars may be brought closer together orfarther apart which thus causes portions of the peripheries of thebreaker roller 75 to move accordingly into or out of the path of papertravel. Thus this mere action of turning the thumb screw whichvertically adjusts the mounting bar will adjust the breaker rollers aswell. With a portion of the peripheries of the rollers '75 extendingslightly above the line of paper travel, the stationery passing throughthe burster is caused to be defiected slightly upward at that point.Such vertical defiection will cause an increase in the tension in thestationery. As the transverse line of weakening passes the point of thebreaker rollers the driving engagement of the rear roller unit willcause the stationery to be progressively torn evenly along that line ofweakening creating the burst or separation of the individual formlengths from the remainder of the continuous form stationery.

Extending in the direction of paper travel and positioned above andbelow the line of paper travel is the paper guide means 14. The guidemeans 14 consists of two rigid elongate generally arcuate members ofsheet metal 80 and 82 which are positioned above and below the path ofpaper travel, respectively, to form a paper guiding channel. The upperguiding member 80 has a front upturned end 80a which is secured ateither side to the interior side of the wall of the burster as at 83 anda similarly upturned rear end 8011 which extends around the periphery ofthe rear roller 37 and is similarly secured to the interior of theburster wall as at 83a. Accordingly, the lower paper guiding member 82has a similarly downturned front end 82a secured at either side to theinterior walls of the burster as at 84 and a downturned rear end S2bextending around the periphery of the roller 37 and secured at eitherside to the interior of the rearward wall of the burster as at 84a. Theoutturned front ends 80a and 82a of the upper and lower guiding memberscooperate to form the aforementioned front infeed channel 15 throughwhich the stationery passes as it is fed into the burster. The channel15 forms a restricted infeed passage which tends to smooth outstationery entering the burster.

Each guide means 80 and S2 is cut away in the body portion to form aseries of rigid bars 35 laterally spaced from each other and extendinggenerally in the direction of paper travel. Each bar 8S extendscontinuously throughout the path of paper travel through the burster,passing through the roller unit 16 and 17 in the recessed areas 37 ofthe individual rollers. The closely spaced bar elements S5 of the guidemeans 30 and 82 dampen the vertical movement of the stationery 12awithout substantially limiting the horizontal movement thereof.

As stationery is fed into the front end of the burster it is directedthrough the channel 15 and thence continuously supported from below andconfined from above by the spaced bars S5 throughout its path of travelthrough the burster. Thus the paper guide means 14 aids the flow ofpaper through the burster and also promotes the constant feedingthereof.

This new and improved burster provides a means for maintaining aconstant rate of paper feed by providing for two sets of rollers havingfiat portions thereon with the sets of rollers being timed in reverseproportion to the number of flats on each set. The two sets of rollersmay be positioned at different spaced distances to accommodate differentform lengths of stationery by simple means which does not interfere withthe timed relationship therebetween. Mere application of hand pressureand release thereof will adapt the front set of rollers for swingingabout an arc parallel to the line of paper travel and thence lock therollers at any preselected position along the aforementioned path ofpaper travel. This simple positioning and self-locking means does notrequire the use of any auxiliary motors or complicated gearingmechanisms. The front and rear set of rollers are driven from al commonsource and they receive their motive power along two independentchannels, thus allowing this adjustment to take place withoutinterfering with the aforementioned timed relationship therebetween.This burster is also provided with a means for guiding the paper alongits path throughout the machine so as to minimize vertical deflectionand thus substantially eliminate buckling in the stationery. Thevertically adjustable breaker roller allows the burster to beindependently adjusted to conform to the tensions of various types ofstationery which may be fed therethrough and thus improve the burstingaction. Moreover the individual sets of rollers may be adjusted so thatthe relative distance between the peripheries thereof may be made toconform vto the thickness of the stationery being processed by theburster.

The foregoing detailed description has been given for clearness ofunderstanding only, and no unnecessary limitations should be understoodtherefrom, for some modifications will be obvious to those skilled inthe art.

I claim:

l. A bursting machine for bursting continuous form stationery into formlengths between transverse lines of weakening, comprising; a base frame,a first pair of coacting driven rollers mounted in said frame, saidrollers having adjacent surfaces with a plurality of longitudinallyextending flats formed thereon, said first pair of coacting rollersbeing geared together for rotation at a common peripheral rate; apivotally mounted arm extending substantially normal to the direction ofpaper travel; a second pair of coacting driven rollers operativelymounted on said arm, said second pair of rollers having adjacentsurfaces and also having a plurality of longitudinally extending flats,said second pair of rollers being driven at a reduced speed relative tosaid first pair of rollers, the ratio of the speed of said first andsecond rollers being inverse to the ratio of the number of fiats on saidfirst to the number of flats on said second rollers.

2. The device of claim 1 wherein said pivotally mounted arm is movableas a unit in the direction of paper travel so that movement of said armwill not turn the second pair of rollers and therefore the timedrelationship between said first and second pairs of rollers ismaintained upon movement of the arm in the direction of paper travel.

3. In a bursting machine having first and second pairs of driven rollersdriven at different speeds, means for mounting one of said pairs ofrollers for movement relative to the other pair comprising a pivoted armin which said one pair of rollers is journaled.

4. In a bursting machine having a first pair of driven rollers mountedin said frame and a second pair of rollers driven at a reduced speedrelative to said first pair of rollers, a pair of pivoted arms formounting said second pair of rollers for lateral movement relative tosaid first pair of rollers to adjust said macine for bursting stationeryof different form lengths.

5. In a bursting machine having a frame, a first pair of driven rollersmounted in said frame, said first pair of rollers having longitudinallyextending fiats thereon, and a second pair of rollers having a pluralityof longitudinally extending flats thereon and driven at a timed reducedspeed relative to said first pair of rollers, the number of flats onsaid rst and second rollers being in inverse ratio to the speed thereof;a pair of pivoted arms for mounting said second pair of rollers formovement relative to said first pair of rollers to adjust said machinefor bursting stationery of different form lengths without disturbing thetimed relationship of said pairs of rollers.

6. In a bursting machine having a frame, a first pair of driven rollersmounted in said frame, said first pair of rollers having longitudinallyextending flats thereon, and a second pair of rollers having a pluralityof longitudinally extending flats thereon and driven at a timed reducedspeed relative to said first pair of rollers, the number of flats onsaid first and second rollers being in inverse ratio to the speedthereof, a pair of pivoted arms for mounting said second pair of rollersfor lateral movement relative to said first pair of rollers to adjustsaid machine for bursting stationery or different form lengths withoutdisturbing the timed relationship of said pairs of rollers, and lockingmeans mounted on said arms and normally urged in locking engagement withsaid frame to lock said pivoted arms and position the rollers atselected positions along the path of stationery travel spaced from saidfirst pair of rollers, said locking means being releasable uponactuation thereof to move said arms and adapted to automatically engagein locking relation with said frame upon termination of release thereof.

7. The bursting machine of claim 6 wherein said locking means includes aspring loaded member normally in frictional engagement with said frame,said member being manually compressible to permit movement of said armsand said second pair of rollers in selected positions along the path ofpaper travel and adapted to frictionally engage said frame in lockingengagement thereto upon release thereof.

8. In a bursting machine for bursting continuous form stationery intoform lengths, a frame, driving means in said frame, a first pa-ir ofrollers driven by said driving means, said first pair of rollers havinglongitudinally eX- tending flats thereon, a second pair of rollershaving a plurality of longitudinally extending flats thereon and drivenby said driving means at a timed reduced speed relative to said firstpair of rollers, the number of fats on said first and second pairs ofrollers being in inverse ratio to the speed thereof; a pair of pivotedarms for mounting said second pair of rollers for movement relative tosaid first pair of rollers to adapt said machine for bursting stationeryinto different form lengths without disturbing the timed relationship ofsaid pairs of rollers.

9. The bursting machine of claim 8 wherein said means for driving saidrollers includes a driven shaft positioned in the pivotal mounting forsaid arms and about which said arms are rotatable relative thereto, oneend of said shaft having a pulley thereon; one end of each of said pairsof rollers also having a pulley thereon for receiving a driving forcefrom said driven shaft through an interconnecting belt, so that `thetimed relationship between said first and second pair of rollers will bemaintained as said second pair of rollers is moved in the direction ofpaper travel by swinging said arms about said pivotal mounting to adaptsaid machine for bursting stationery of different form lengths.

10. The bursting machine of claim 9 including locking means for lockingthe pivoted arms to secure the rollers at selected positions along thepath of stationery travel comprising: a spring loaded member normally infrictional engagement with said frame, said member being manuallycompressible to permit movement of said arms and said second pair ofrollers in selected positions along the path of paper travel and adaptedto frictionally engage said frame in locking engagement upon releasethereof.

l1. A bursting machine for bursting continuous forni stationery intoform lengths between transverse lines of weakening, comprising: a frame;driving means in said frame including a driving shaft generallytransverse to the path of stationery travel through the machine; sidepanels mounted to said frame outside the path of stationery travel, eachside panel having a relatively wide arcuate slot therein extendinggenerally parallel to the path of stationery travel; a first pair ofstationery rollers driven by said driving means, said rollers beingmounted in said slots in said frame generally transverse to the path ofpaper travel and having longitudinally extending flats thereon; a secondpair of rollers mounted in said frame transverse to the path ofstationery travel and across said slots in said side panels having aplurality of longitudinally extending ats thereon and driven by saiddriving means at a timed reduced speed relative to said first pair ofrollers, the number of fiats on said first and second pairs of rollersbeing in inverse ratio to the speed thereof; a pair of arms pivoted tosaid drive shaft and positioned outside said side panels for mountingsaid second pair of rollers for movement in rsaid slots relative to saidfirst pair of rollers; means interconnecting one end of said drive shaftto said first pair of rollers and the other end of said dr-ive shaft tothe second pair of rollers so that movement of said arms to move saidsecond set of rollers to adapt said machine for bursting stationery ofdifferent form lengths will not disturb the timed relationship of saidrollers; and locking means on said second set of rollers including apair of spaced bars pivoted to the second set of rollers and beingnormally urged apart by a spring interposed therebetween, said barshaving surfaces at either end thereof normally in frictionally lockingengagement with said slot in response to the urging of said spring; saidspring further being manually compressible to move said bars toward eachother and out of frictional locking engagement with said slot to permitmovement of said arms and said second pair of rollers to selectedpositions along the path of stationery travel and automatically movingsaid bars in frictional locking engagement with said slot upon therelease of said spring.

References Cited in the file of this patent UNITED STATES PATENTS2,252,736 Sherman et al Aug. 19, 1941 2,375,542 Euth May 8, 19452,380,949 Davidson Aug. 7, 1945 2,513,093 Hageman June 27, 1950

1. A BURSTING MACHINE FOR BURSTING CONTINUOUS FORM STATIONERY INTO FORMLENGTHS BETWEEN TRANSVERSE LINES OF WEAKENING, COMPRISING; A BASE FRAME,A FIRST PAIR OF COACTING DRIVEN ROLLERS MOUNTED IN SAID FRAME, SAIDROLLERS HAVING ADJACENT SURFACES WITH A PLURALITY OF LONGITUDINALLYEXTENDING FLATS FORMED THEREON, SAID FIRST PAIR OF COACTING ROLLERSBEING GEARED TOGETHER FOR ROTATION AT A COMMON PERIPHERAL RATE; APIVOTALLY MOUNTED ARM EXTENDING SUBSTANTIALLY NORMAL TO THE DIRECTION OFPAPER TRAVEL; A SECOND PAIR OF COACTING DRIVEN ROLLERS OPERATIVELYMOUNTED ON SAID ARM, SAID SECOND PAIR OF ROLLERS HAVING ADJACENTSURFACES AND ALSO HAVING A PLURALITY OF LONGITUDINALLY EXTENDING FLATS,SAID SECOND PAIR OF ROLLERS BEING DRIVEN AT A REDUCED SPEED RELATIVE TOSAID FIRST PAIR OF ROLLERS, THE RATIO OF THE SPEED OF SAID FIRST ANDSECOND ROLLERS BEING INVERSE TO THE RATIO OF THE NUMBER OF FLATS ON SAIDFIRST TO THE NUMBER OF FLATS ON SAID SECOND ROLLERS.